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HANS HEINRICH EGGEBRECHT
Jam session [Jam].
An informal gathering of jazz or rock musicians playing for their own pleasure. Jam sessions originated in the 1930s as spontaneous diversions among jazz musicians, free from the constraints of professional engagements; they also served the function of training young musicians in a musical tradition that was not formally taught and accepted in music schools and academic institutions until the 1960s. In the late 1930s jam sessions came to be organized by entrepreneurs for audiences; this undermined their original purpose, and by the 1950s true jam sessions were becoming increasingly rare. However, in the 1970s and 80s jam sessions made a comeback among younger jazz musicians, especially those trained in conservatories. The loft scene of the late 1970s, so-called because of its establishment of abandoned lofts as concert venues in the Village in New York, can also be seen as a quasi-commercial offshoot of the jam session. The idea of a jam session, or simply jamming, has come to mean any meeting of musicians, in private or public, where the emphasis is on unrehearsed material and improvisation.